Private Sub Worksheet_Change(ByVal Target As Range)
MsgBox Intersect(Target, [A:A], UsedRange).Address
Set Target = Intersect(Target, [A:A], UsedRange) 'à adapter
If Target Is Nothing Then Exit Sub
Application.EnableEvents = False
Target.NumberFormat = "General" 'format Standard
For Each Target In Target 'si entrées multiples (copier-coller)
If Target Like "########" Then If IsDate(Format(Target, "00\/00\/0000")) Then _
Target = CDate(Format(Target, "00\/00\/0000")): Target.NumberFormat = "dd/mm/yyyy"
Next
Application.EnableEvents = True
End Sub